Husband won’t let me go down on him

My husband and I used to do all of that when he were just boyfriend and girlfriend (we’re 22 and 23) and he loved sex but now I’m 28 weeks pregnant and we rarely have sex. Last time we did it was in December (just once) and I tried going down on him but he stopped me. I understood because he said he hadn’t showered. He has been gone for 2 weeks (he’s a Marine) and we’d text saying how we want to make love and I even told him I wanna go down on him and he seemed into it. Well last night he was showering and I decided to put on some sexy undies and a flannel that’s big on me and wait for him on the bed. When we finally start things he tells me he doesn’t want to end up feeling the baby kick. This time I asked if I could go down on him and he didn’t seem to want it. I wanted to get wet for him so I used my vibrator really quick and stroke his dick but he didn’t seem to be liking that so I just let him do it. It felt so awkward 😩 I felt like shit. We ended up just doing doggie. Now I feel like there’s something wrong with me